1. Field of the Invention
This invention involves a reinforced laminated beam, and, more particularly, a glued laminated wood beam wherein high strength reinforcing material in continuous form is adhesively positioned between laminations in locations of high stress.
2. Description of the Prior Art
The glued laminated wood beam has a number of properties which make it superior for structural applications:
a. Such beams are reliable, dimensionally stable and long-lasting
b. They are economical, usually being lower in cost than steel, have a high strength-to-weight ratio and are easy to modify on-site.
c. They are safe, in that such beams burn slowly and resist heat penetration by the formation of char, allowing the uncharred inner portion to maintain its strength; and do not deform significantly in a fire. Furthermore, they can absorb shocks that would rupture or break other materials, thus providing safety under high wind and earthquake conditions.
d. They offer the natural beauty of wood.
There is a need, however, to improve the tensile strength of glued laminated wood beams without affecting the advantages in their use, particularly the flexibility of on-site modification. The maximum tension, in the normal beam application, occurs along the lower laminations of the beam, thus establishing the carrying capacity of the conventionally constructed beam.
An increase in beam strength, particularly at the lower laminations, would permit greater loads to be placed on the beams, or in the alternative, would allow a smaller beam to carry the same load. The latter provides architectural advantages by permitting a shallower beam in designs where beam space is at a premium.